Ku波段同轴渡越辐射振荡器的数值模拟

当传统高功率微波器件向高频段拓展时,器件尺寸的缩小将造成空间极限电流及功率容量的减小。基于此提出一种Ku波段同轴结构的渡越辐射振荡器。通过引入同轴结构,器件内部的空间极限电流及功率容量得到了有效提升。调制腔采用三谐振腔结构,与两腔结构相比,调制电子束的能力明显增强。采用高频场软件对调制腔和输出腔进行了冷腔分析。利用2.5维粒子模拟软件对Ku波段同轴渡越辐射振荡器进行了数值模拟,在导引磁场0.6 T、二极管电压392 kV、电流15.2 kA的条件下,在中心频率为14.184 GHz处获得1.2 GW的高功率微波输出,功率转换效率达20%。

Numerical simulation on Ku-band coaxial transit-time oscillator

When the operating frequency goes into higher band, the traditional high power microwave (HPM) generators are of smaller size and can support less power capacity and space-charge limiting. In order to solve these difficulties, a Ku-band coaxial transit-time oscillator was proposed. Using a coaxial structure, the space-charge limiting current and power capacity of the proposed device can be increased significantly. In comparison with a dual-cavity buncher, this proposed device with a trinal-cavity buncher can lead to a higher degree of beam current modulation. By using high frequency field software, the cold-cavity analysis was performed for buncher and extractor. The proposed oscillator was designed and optimized by a particle-in-cell (PIC) code. With the voltage 392 kV, the current 15.2 kA and the guiding magnetic field 0.6 T, the output power was 1.2 GW at the main frequency 14.184 GHz, and the efficiency of beam-to-microwave power conversion was about 20%.